New York Islanders' Thomas Hickey (14) and New Jersey Devils' Stephen Gionta collide against the boards in the third period of an NHL hockey game on Dec. 28. The Devils won 2-1. Photo: AP Photo/Kathy Kmonicek

On Saturday, the Islanders found out what they likely already were aware of: winning without their best player won’t be easy.

Still, the Isles tied the game at 1-1 when Frans Nielsen — in Tavares’ spot at center of the top line — scored on a pass from Kyle Okposo at 10:31 of the third period.

But less than three minutes later, the Devils regained the lead for good, when Marek Zidlicky’s slap shot was drilled off Travis Zajac’s left shoulder and got by Evgeni Nabokov at 13:03.

“Any coach will tell you go to the middle of the net,” Nabokov said of Zajac’s efforts. “He paid his price. He worked hard for that goal.”

Zajac had to be helped from the ice after the goal.

“I might have been a little overdramatic there, because a couple of minutes later, I felt all right,” Zajac said.

The goal was set up by Jaromir Jagr, unrushed as he let the play develop before finding Zidlicky.

“[Jagr] looked like he was back in ’95,” Zajac said. “Just all time in the world and waving to fans with the puck. He’s dangerous when he gets in the offensive zone.”

Without Tavares, the Islanders were left with even less margin for error than usual and their efforts to get out of the cellar will become that much more difficult if he is out for any length of time.

On Saturday, though, the Isles believed they had a shot to overcome his absence.

“That type of thing where, ‘Oh, we played well,’ doesn’t cut it anymore,” Nabokov said. “It’s kind of old music for us. We play well but can’t catch a break. Well, we have to find a way to catch a break. That’s what the good teams do.”

That didn’t happen Saturday, even after Nielsen gave the Isles new life when he took over at center on the top line, replacing the ineffective Brock Nelson.

The loss dropped the Islanders to 11-21-7, while the Devils improved to 16-16-8 in front of 16,012 at the Nassau Coliseum.

The absence of Tavares was somewhat expected after he missed practice on Friday with the same injury.

Capuano said the injury didn’t occur during the Isles’ victory over the Red Wings in Detroit on Monday and instead was something that has lingered for a while.

The captain has a team-high 39 points, with 13 goals and 26 assists and his presence certainly would have helped a power play that failed to generate much in four opportunities.

“I think the young guys struggled today,” Capuano said. “It’s a process. We’re going to go through some growing pains.”